Accessory for carburetors for engines

ABSTRACT

A carburetor structure provides additional air during engine idling at the idling fuel inlet, and additional air during engine acceleration away from the idling fuel inlet. Provision of additional air at these locations helps to break up fuel condensate, and thus improve combustion.

iliiited States Patent [1 1 August 1 Oct. .30, 1973 1 1 ACCESSORY FOR CARBURETORS FOR ENGINES [76] Inventor: Paul August, Capellades 1,

vli iq lgnaac pa [22] Filed: Apr. 2, 1970 [21] Appl. No.: 25,279

Related U.S. Application Data [63] Continuation-impart of Ser. No. 618,028, Feb. 23,

1967, abandoned.

[30] Foreign Application Priority Data Jan. 9,- 1967 Germany A 54 567 [56] References Cited UNITED STATES PATENTS 1,271,541 7/1918 Core et a1. 123/119 B 1,331,856 2/1920 Summers... 123/122 F 1,684,246 9/1928 Salva 261/142 2,057,215 10/1936 Smith 261/41 2,139,801 12/1938 Boyce 123/119 B 2,809,623 10/1957 Hall 123/97 B X 2,833,261 5/1958 August 123/122 2,868,182 11/1959 Cornelius 123/97 B 2,877,753 3/1959 Larsen 26l/DIG. 20 2,928,662 3/1960 August... 261/41 3,059,628 10/1962 Linn 123/119 B 3,168,085 2/1965 Stelter.... 48/180 UX 3,174,469 3/1965 Rappolt 123/119 1,562,077 l1/l925 Blifl'ert 48/180 R 2,433,205 12/1947 Decker 261/41 D 2,479,852 8/1949 McDonnell 48/180 R X FOREIGN PATENTS OR APPLICATIONS 3,728 1 1914 Great Britain 137/480 Primary ExaminerTim R. Miles Attorney-Jeffers and Rickert [57] ABSTRACT A carburetor structure provides additional air during engine idling at the idling fuel inlet, and additional air during engine acceleration away from the idling fuel inlet. Provision of additional air at these locations helps to break up fuel condensate, and thus improve combustion.

8 Claims, 3 Drawing Figures Patented Oct. 30, 1973 INVENTOR PAUL A0605? fiw MK ATTORNEY ACCESSORY FOR CARBURETORS FOR ENGINES CROSS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of U. S. Pat. application Ser. No. 618,028, filed Feb. 23, 1967 now abandoned.

SUMMARY OF THE INVENTION The subject of the present invention is an accessory device which is mounted on the lower part of the car buretor or contained in the base of the carburetor.

This device serves for treatment of the fuel condensate especially in idle running, in the lower speed and load range as also in acceleration. However, the nonuniform formation of the mixture, which occurs in the carburetor under different operating conditions, is avoided by this device, and in addition in the valve operation the idler jet is shut off and a further step taken to reduce the formation of noxious gases in the valve operation of internal combustion engines.

BRIEF DESCRIPTION OF THE DRAWING In the accompanying drawings FIG. 1 shows a device according to the invention located at the lower end of a carburetor;

FIG. 2 is a section on the line A-B of FIG. 1, while FIG. 3 is a section on the line CD of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT The main foundation of condensate in the carburetor system of an internal combustion engine occurs in the lower speed and load range in conjunction with the very rich fuel-air mixture from the idling system. This fuel-air mixture flows as a fluid condensate beneath the wall of the carburetor and normally reaches the engine very slightly mixed with air. In order to destroy this condensation there is provided on the right hand side of the device a nose 1 with a breaking-up edge 12. Similarly, the left hand side of the device is provided with a nose 33 having a break up edge 34. Combustion air is supplied by way of an inlet passage 3 and a passage 2 and passes out through a gap 4 beneath the nose 1. Regulation of the quantity of combustion air which reaches the gap 4 is possible by means of a regulating screw 5.

When the throttle valve of the carburetor is in idle running position there is provided, at the right side at which the passages for the idle running system of the carburetor are located, a very rich mixture while at the opposite or left side pure air enters through a gap in the throttle valve. In order to balance the non-uniform mixture, in this invention fuel vapours forming in the crank chamber are supplied by way of an inlet passage 6 and a passage 7 and a gap 8 on the opposite side of the gap 4 to the flow of mixture. As a result the otherwise pure air at this side receives an addition of fuel vapours and the mixture formation becomes more uniform than it would be without this step.

So far then, the extension of the carburetor bore is seen to be provided with a pair of opposed slits 4 and 8 having a pair of overhanging noses l and 33, each of the overhanging nose portions being provided with a break up edge 12, or 34.

A valve 9 with a spring 10 interrupts the inlet passage 6 and closes this at normal negative pressure. If on acceleration the negative pressure is very small or is nonexistent, the suction action through the passage 11 on the valve 9 is reduced and the spring 10 presses the valve 9 to the left (as viewed in FIG. 1) so as to open the passage from the passage 3 to the passage 7. In this case during acceleration additional combustion air passes to the gap 8. During acceleration the accelerator pump sprays a strong stream of fuel to the side of the carburetor beneath which the gap 8 is located so that fuel condensation is formed on the carburetor wall, which condensation is broken up at the lower end of the break-up edge 34 where combustion air is supplied behind the said edge by way of the passages 3 and 7. If acceleration is interrupted the negative pressure becomes greater and the valve 9 closes the passage from 3 to 7. As a result the supply of combustion air to the gap 8 continues only so long as the accelerator pump sprays a fuel stream on the side of the carburetor and also provides the carburetor side wall beneath which the gap 8 is located with condensate.

In operation of the valve a very strong suction is extracted on the idling-mixing system of the carburetor and a very rich mixture in large quantity flows from the idler to the engine which is provided only to a small extent with combustion air. During this operation of the valve in the first few seconds pure fuel vapour (CH) flows from the exhaust as no combustion takes place. Later (CO) is added as partial combustion takes place. In this invention a piston valve 13 is provided in a cylinder 14 which is held by a spring 15 and an adjustment nut 16 in its upper end. Beneath the piston is located a somewhat softer packing 17 and a passage 18 which is connected with a negative pressure passage 19. The spring tension is so held by means of the adjusting nut 16 that in idle running and in normal operation the piston remains in its upper postion. In operation of the valve the negative pressure increases very strongly and pulls the piston 13 down on its lower packing 17. As in this moment the air, which can otherwise flow between the piston and cylinder, is interrupted by the piston resting on the packing, the negative pressure acting on the piston bottom increases and the piston is held fast against the packing 17. In the cylinder is inserted a sleeve 19a with two opposed slits 20. At the level of these slits is provided on the one side an inlet bore 21 and on the other side a bore 22. The piston has an annular groove 23 which in the lower position of the piston registers with the slits 20 in the sleeve 19a. The bore 22 is connected with the passage 7.by means of a bore 24. The piston with its piston rod 25 actuates an electric switch 26, 27 in such manner that in the upper positon of the piston the switch is closed and in the lower position of the piston the switch is open. The switch 26, 27 is located in the circuit of an electromagnetic locking device for an electromagnetic idling jet 28 in such manner that with the switch open current to the locking device is switched off and the flow of fuel to the jet is interrupted.

If now, in operation of the valve the piston 13 is drawn downwards, for example when the throttle is opened wide, it interrupts, not only the flow of fuel in the idling system of the carburetor, but allows additional combustion air into the passage 7 by way of the bore 21, slits 20, bores 22 and 24, from which this combustion air flows by way of the gap 8 into the suction system of the motor. On sudden closing of the throttle valve and therewith the beginning of movement of the valve 9 there flows through the raised throttle valve,

mainly to the side of the passages on which the gap 8 is provided, additional fuel from the main jet system, and it is important that this fuel (1) is broken up on the edge and (2) is provided additionally with combustion air. By these measures and by the closing of the idling jet the formation of noxious uncondensed or only partly consumed hydro-carbons is cut off seconds earlier than by closing the idling jet alone.

in recapitulating the following may be stated:

It is not sufficient for example to supply additional air or additional gas under the carburetor at the side where the idling system is located. it is necessary that at this side the projecting nose 1 is formed so that the condensate at the lower end of this nose, that is at the break up edge 12, is torn up into the free space. It is moreover necessary that directly under and behind this nose additional combustion air is supplied in such manner that first of all a stream of air is laid between the broken up condensate and the wall and in the second place that the condensate at the moment of being broken up is between two air streams whereby it is accelerated about 500 fold and thus dynamically treated.

There is no object in idle running, and at low reduction load, to supply combustion air to the whole periphery beneath the carburetor. This would not get rid of the non-uniformity of the mixture. It is of the greatest importance that in this range combustion air should be supplied only to the idling side of the system.

On the contrary the uniformity of the formation of the mixture is improved additionally by supplying fuel vapour to the opposite side as in this invention. As already set forth earlier, in the idling and lower range only pure combustion air enters through the slit in the closed or slightly opened throttle valve. it is thus wholly wrong, by an additional air supply, to increase: this nonuniformity of mixture formation.

As at the moment of acceleration, particularly on the side of the carburetor remote from the idling system, condensate forms on the wall which lies on the construction of the carburetor or on the position of the throttle valve, it is of the highest importance that at this moment on the side remote from the idling system condensate-treatment with additional air is carried out.

It is already known that in the operation of the valve the fuel supply should be cut off. An additional improvement is provided by the simultaneous opening of the passage for combustion air which in the first few seconds leads to better combustion of the flowing fuel than without this measure.

It is essential also that the fuel, particularly for the idling side, should be heated. According to the invention there is provided in front of the inlet passage 3 an air filter 29 with an electrical heating coil or alternatively this air filter is heated by exhaust gases through an inlet 31. Electrical heating is more efficient, as particularly with a cold motor, the treatment of the condensate must be more intense than with a warm engine. it is preferable to effect the preheating with a manually or thermostatically actuated switch 32and to wait several seconds before starting the engine. As a result the usual enrichment of the mixture with a cold start is much reduced resulting in a saving in fuel and above all increasing the life of the motor.

Tests with a known 4 cylinder engine of 1600 c.c. has given the following results (carried out according to the seven part California cycle). Original factory adjustment 33% CO 702 ppm CH Factory setting reduced 1 l 3. 2. CO 690 ppm CH 1.49% CO 626 ppm CH 08% CO 492 ppm CH 0.8% CO 300 ppm CH In this device the balance of the idling mixture was not effected by adding fuel vapours and the supply of additional air.

On the bases of the test results it was reckoned that with the use of all the measures the CO would be under 0.5 percent and the CH under 250 ppm. The tests at the several stages were given in order to show that advantages are attained by the additional measures on the combustion and thus reduction of poisonous gases with the device of this invention. Devices produced hitherto for providing additional air have given no result which could not be obtained by adjustment of the carburetor. This is the first device which provides for conversion of the condensate and formation of the mixture and actual advantages are obtained which are not possible by regulation of the carburetor alone.

I claim 1. An accessory to be positioned directly beneath a carburetor for an internal combustion engine having an idle running fuel inlet comprising:

a. a plate having an opening therethrough for passing air from said carburetor to said engine;

b. said plate opening being formed by first and second break-up edges positioned on opposite sides of said opening, said first break-up edge lying directly beneath said idle running fuel inlet;

c. said plate having first and second air slits positioned beneath said first and second break-up edges respectively for supplying air to said plate opening;

. said plate having an air inlet for said accessory;

e. said plate having a first air passage for permanently connecting said air inlet to said first air slit;

f. said plate having a second air passage for selectively connecting said air inlet to said second air slit;

g. and a spring loaded separating valve positioned hid second air passage responsive to changes in the relative air pressure within said plate opening to selectively pass and block the flow of air from said air inlet to said second air slit.

2. The accessory of claim 1, and further comprising a regulating screw inserted in said first air passage.

3. The accessory of claim 1 having means connecting said spring loaded separating valve to said plate opening to close said spring loaded separating valve at a normal negative pressure and open said spring loaded separating valve at a small negative pressure to provide an air path through said second air passsage.

4. The accessory of claim 1, and further comprising a second inlet connected with said second air passage for connection to said engine for receiving fuel vapor.

5. The accessory of claim 1, and further comprising a spring loaded piston connected by a third air passage to said plate opening.

6. The accessory of claim 5 wherein said spring loaded piston comprises an annular groove which, in said second position of said spring loaded piston, opens a passage for combustion air by way of a third inlet passage, a slit surrounding said spring loaded piston, and passages to said second air slit.

7. The accessory of claim 1 wherein said air inlet comprises a threaded part having an electric heating spiral.

8. The accessory of claim 7 further comprising means for providing said electric heating spiral with current in response to the ignition of said engine being turned on. 16K i t UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 ]68 789 Dated October 30 1973 lnventofl Paul August It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 4-, line 39, (Claim l) "in" omitted after positioned" Signed and sealed this 2nd day of April 1971;.

(SEAL) Attest:

EDWARD B'E.FLETGHER,JR. C. MARSHALL DAMN Attesting Officer Commissionerof Patents 

1. An accessory to be positioned directly beneath a carburetor for an internal combustion engine having an idle running fuel inlet comprising: a. a plate having an opening therethrough for passing air from said carburetor to said engine; b. said plate opening being formed by first and second break-up edges positioned on opposite sides of said opening, said first break-up edge lying directly beneath said idle running fuel inlet; c. said plate having first and second air slits positioned beneath said first and second break-up edges respectively for supplying air to said plate opening; d. said plate having an air inlet for said accessory; e. said plate having a first air passage for permanently connecting said air inlet to said first air slit; f. said plate having a second air passage for selectively connecting said air inlet to said second air slit; g. and a spring loaded separating valve positioned said second air passage responsive to changes in the relative air pressure within said plate opening to selectively pass and block the flow of air from said air inlet to said second air slit.
 2. The accessory of claim 1, and further comprising a regulating screw inserted in said first air passage.
 3. The accessory of claim 1 having means connecting said spring loaded separating valve to said plate opening to close said spring loaded separating valve at a normal negative pressure and open said spring loaded separating valve at a small negative pressure to provide an air path through said second air passsage.
 4. The accessory of claim 1, and further comprising a second inlet connected with said second air passage for connection to said engine for receiving fuel vapor.
 5. The accessory of claim 1, and further comprising a spring loaded piston connected by a third air passage to said plate opening.
 6. The accessory of claim 5 wherein said spring loaded piston comprises an annular groove which, in said second position of said spring loaded piston, opens a passage for combustion air by way of a third inlet passage, a slit surrounding said spring loaded piston, and passages to said second air slit.
 7. The accessory of claim 1 wherein said air inlet comprises a threaded part having an electric heating spiral.
 8. The accessory of claim 7 further comprising means for providing said electric heating spiral with current in response to the ignition of said engine being turned on. 